The present invention relates generally to transistors and, more particularly, to transistors based on tunneling structures and their applications.
Tunneling hot electron transistor amplifiers including a metal-insulator-metal-insulator-metal (M-I-M-I-M) configuration was first proposed by Mead in 19601 and analyzed in detail by Heiblum in 1981.2 Turning now to the drawings, wherein like components are indicated by like reference numbers throughout the various figures where possible, attention is immediately directed to FIG. 1, an exemplary M-I-M-I-M transistor of the prior art is illustrated. It is noted that the figures are not drawn to scale for purposes of clarity.
FIG. 1 illustrates a partial cross sectional view of a typical M-I-M-I-M transistor, generally indicated by a reference numeral 100. M-I-M-I-M transistor 100 includes alternating single layers of metals and insulators, including an emitter electrode 110, a base electrode 112, a collector electrode 114, an emitter barrier 116, and a collector barrier 118.
Other researchers have investigated similar transistor structures using epitaxial metal-insulator structures3, III–V semiconductor structures4a,4b, and structures using ferromagnetic metals4c and insulators4d.
Additionally, in many circuit applications, it is advantageous to have complementary pairs of transistors such that one transistor turns on with positive base-emitter voltage and another, complementary, transistor turns on with negative base-emitter voltage. In this way, a push-pull amplifier or switch circuits may be built. Examples of such devices include silicon CMOS or bipolar push-pull power amplifiers, which use relatively low quiescent power.
Prior art hot hole transistors8 have the same M-I-M-I-M as the previously described hot electron transistors. Device operation is also similar, with the exception that holes, instead of electrons, are the charge carriers in the device. However, the hot hole transistors of the prior art share the same problems as in prior art M-I-M-I-M hot electron transistors.
As will be seen hereinafter, the present invention provides a remarkable improvement over the prior art as discussed above by virtue of its ability to provide fast thin-film devices with increased performance while resolving the aforedescribed problems present in the current state of the art.